fortune:tldr:13c44

The command "fortune -f" is used to display a list of categories available for the 'fortune' command.

The 'fortune' command is a utility that displays random quotes, sayings, or jokes on the command-line interface. These quotes are stored in text files categorized by themes or topics like literature, humor, science, and more.

By entering "fortune -f", the command will retrieve a list of available categories without actually displaying any quotes. This gives users an overview of the categories they can choose from when running the 'fortune' command with a specific category.

For example, if you want to display a random quote from the "literature" category, you can use the "fortune literature" command. The "-f" option is handy to check available categories before using the 'fortune' command.